SEXIEST GEEK

1985: Boyishly cute Michael J. Fox lent hipster cred to young Republicanism (as Alex P. Keaton on Family Ties) and weird science (as Marty McFly in Back to the Future).

2005: With his indie-rock and comic-book obsessions, The O.C.'s own loveable misfit, Adam Brody, has made fast-talking fanboys hot. "The giggling, the pointing – girls freak out over him," one producer told PEOPLE.